4,4'-DIISOPROPYLBIPHENYL PRODUCTION PROCESS Russian patent published in 2008 - IPC C07C15/14 C07C2/66 C07C39/12 

FIELD: industrial organic synthesis.

SUBSTANCE: invention relates to technology of alkylation of aromatic compounds by lower olefins using zeolite catalysts, in particular to continuous process of high-selective isopropylation of biphenyl to produce 4,4'-diisopropylbiphenyl. Biphenyl and propylene dissolved in decaline are passed through solid zeolite catalyst bed at 180-220°C and pressure 10-30 atm. Zeolite catalyst is, more particularly, acid zeolite catalyst with SiO₂/Al₂0₃ molar ratio from about 20:1 to about 500:1. Optimally, 35% or more of active sites of catalyst are characterized by ammonia desorption activation n energy between 145 and 170 kJ/mole. Acid zeolite catalyst is prepared via dealumination of a zeolite precursor by bringing the latter into contact with an aqueous acid, said zeolite precursor being selected from mordenite, mazzite, and beta-zeolites. Dealumination step includes heat treatment with water steam for at least two hours at temperature from 550 to 800°C. Preferably, acid zeolite catalyst, before dealumination reaction, is pretreated with a volatile basic agent at 0 to 500°C and pressure from 0.1 torr to 10 atm.

EFFECT: improved selectivity, quality and stability of product due to improved characteristics of catalyst.

10 cl, 4 tbl, 10 ex